56 lines
1.4 KiB
JavaScript
56 lines
1.4 KiB
JavaScript
|
var baseFindIndex = require('./_baseFindIndex'),
|
||
|
|
baseIsNaN = require('./_baseIsNaN'),
|
||
|
|
toInteger = require('./toInteger');
|
||
|
|
|
||
|
|
/* Built-in method references for those with the same name as other `lodash` methods. */
|
||
|
|
var nativeMax = Math.max,
|
||
|
|
nativeMin = Math.min;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* This method is like `_.indexOf` except that it iterates over elements of
|
||
|
|
* `array` from right to left.
|
||
|
|
*
|
||
|
|
* @static
|
||
|
|
* @memberOf _
|
||
|
|
* @since 0.1.0
|
||
|
|
* @category Array
|
||
|
|
* @param {Array} array The array to inspect.
|
||
|
|
* @param {*} value The value to search for.
|
||
|
|
* @param {number} [fromIndex=array.length-1] The index to search from.
|
||
|
|
* @returns {number} Returns the index of the matched value, else `-1`.
|
||
|
|
* @example
|
||
|
|
*
|
||
|
|
* _.lastIndexOf([1, 2, 1, 2], 2);
|
||
|
|
* // => 3
|
||
|
|
*
|
||
|
|
* // Search from the `fromIndex`.
|
||
|
|
* _.lastIndexOf([1, 2, 1, 2], 2, 2);
|
||
|
|
* // => 1
|
||
|
|
*/
|
||
|
|
function lastIndexOf(array, value, fromIndex) {
|
||
|
|
var length = array ? array.length : 0;
|
||
|
|
if (!length) {
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
var index = length;
|
||
|
|
if (fromIndex !== undefined) {
|
||
|
|
index = toInteger(fromIndex);
|
||
|
|
index = (
|
||
|
|
index < 0
|
||
|
|
? nativeMax(length + index, 0)
|
||
|
|
: nativeMin(index, length - 1)
|
||
|
|
) + 1;
|
||
|
|
}
|
||
|
|
if (value !== value) {
|
||
|
|
return baseFindIndex(array, baseIsNaN, index - 1, true);
|
||
|
|
}
|
||
|
|
while (index--) {
|
||
|
|
if (array[index] === value) {
|
||
|
|
return index;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = lastIndexOf;
|